Górecki's
Concerto
for Harpsichord and String Orchestra (op. 40) is astonishing
music.
The layering of harpsichord and a deep string orchestra
makes for some very complex texture that he accents with intricate rhythms. I
love the simple melodic structure of process music like this concerto but I
can't begin to sort out the harmonies here.

If you've heard of
Henryk
Górecki it's probably because of the
Dawn Upshaw recording of his Symphony
No. 3 that achieved huge popular success a few years ago. Where that
symphony is haunting and lyrical, this 1980 concerto is forceful and
propulsive.

Amazon has a sample of
the recording I have,
see track 5. The dizzying introduction gives a good flavour of the
complexity of the piece. For minimalist music with relatively limited
instrumentation there's a lot going on.